Dental articulator



June 27 1939. R A. PITTMAN ET AL 2,164,144

DENTAL ARTI CULATOR Filed Jan. 28, 195'?` Patented June 27, 1939 DENTALARTICULATOR Ralph A. Pittman, Eldorado, Ark., and Joseph A. Gardner,Memphis, Tenn.

Application January 28, 1937, Serial No. 122,698

5 Claims. (Cl. 32-32) This invention relates to improvements in devicesfor holding models of. portions of the human jaws and teeth inarticulated relation.

It relates to an articulator from which the models may be removed, inorder that they may be worked on or reproduced, and in which the modelsthemselves or reproductions thereof may be again secured, and removed asoften as it may thereafter be found necessary.

It particularly relates to a device of this kind in which upper andlower holder portions of the device or holders, and the models carriedthereby, have relative lateral motion about a central pin and forwardand/or rearward motion relative to each other along the median line ofthe holder.

It further relates to a `device having such relative motions in whichlateral motion also causes a rearward motion, and to a device in whichrearward motion of the upper holder accomplishes a separation of the twoholders and the models carried thereby, and a longitudinal forwardmotion of such holder permits approach of the holders and models carriedthereby.

It further relates to such a device in which the upper and lower holdersnormally remain in a fixed relation, both longitudinally-and laterally.

Articulators have previously been known in which some of the resultsabove enumerated have been accomplished by much more elaborate but lesssatisfactory means.

The objects of. the present invention are:

To provide an articulator having centering means positioned on themedian line of the holders and carried by one thereof, and Iin which theother said holder is oscillatable about said means and longitudinallymovable with regard thereto, both of said movements being resilientlyopposed.

To provide an articulator having a pair of relatively movable modelholders, in which movement, longitudinally and laterally, is centered bya pin carried by one of said holders and in which lateral movement alsocauses a longitudinal movement, all of said movements being resilientlyopposed.

The means by which the foregoing and other objects are accomplished andthe manner of their accomplishment will be readily understood from thefollowing specification on reference to the accompanying drawing, inwhich;-

Fig. 1 is a side elevation of the articulator;

Fig. 2 is a plan view;

Fig. 3 is a corresponding fragmentary section taken on the broken lineIIL-III of Fig. 1;

Fig. l is a fragmentary section taken on the line IV-IV of Fig. 2;

Fig. 5 is a side elevation showing a modified form of the device;

Fig. S is a fragmentary section taken on the 5 line VI-Vl of Fig. 5; and

Fig. 7 is a fragmentary section taken on the line VII-VII of Fig. 5.

Referring now to the drawing, in which the various parts are indicatedby numerals, it and 10 ii are respectively upper and lower holdersadapted to releasably hold models I2 and I3, as of the upper and lowerteeth and related jaw structures. Id is a post integral with andextending upward from the lower holder Il. I5 is 15 a substantiallyhorizontal extension, disposed rearwardly, of the upper end of the postand connected thereto by a short, upwardly inclined portion I6, theextreme rear end of the extension being faced at right angles to thelongitudinal 20 center line of the holder II. Il is a pin rigidlysecured in the extension I5 and extending upward therefrom. Resting onthe upper surface of the extension I5, is a block 20, in which is formeda slot 2|, adapted to slidably receive the 25 pin I'I. At its outer endthis block has a downwardly extending flange 22, adapted to seat againstthe end of the extension I5. 23 is a spring, secured as by screws 24 tothe holder II, the upper end of this spring contacting the rear 3o endof the block 20 and resiliently holding the flange 22 against the end ofthe extension I5.

It will be noted that the width of the rear end of. the extension and ofthe flange are such that any lateral relative movement of the holders 35will shift the upper holder relatively rearward with respect to thelower holder, the slot Il permitting such movement relative to the pin,and that such movement is resisted by the spring 23. This spring, actingagainst the flange 22 tohold 40 the flange against the extension i5,accomplishes the longitudinal centering of the block relatively to thelower holder.

24 is a nut ordinarily loosely contacting the upper surface of the block2l! to hold the same 45 in place, but permitting turning and sliding;and 25 is a lock nut. It will be noted, however, that if it be sodesired these nuts may be used to tightly clamp the block against theupper surface of the extension I5. 5o

The rear end of the upper holder I is forked to provide arms 26, whichare disposed to the opposite sides of the block 20 and are pivotallyconnected thereto, as by screws 2l. 28 is a thumb screw and 29 a locknut therefor, the 55 screw 28 being threadedly screwed through a portionof the holder I0, with its end seated on the inclined portion I6 of theextension I5, and being adjustable to vary the distance between theholders I0 and II 3U are lugs, extending downward from the block 29 onopposite sides of the extension I5, which lugs serve to limit thelateral swing of the block and the upper holder secured thereto,relative to the extension I5 and the lower holder I I.

In Figs. 5, 6 and '7, IIJA and IIA are respectively the upper and lowerholders, I4A the upwardly extending post, IGA the inclined portion ofthe extension IEA, and 23A the spring. In this modification theunderside of the block 20A is chambered out to receive the extensionI5A, thus providing oppositely disposed sides 40 and a rear end 4I, thelatter corresponding to the ange 22. The sides 40 are inwardly thickenedat their forward edges 40A, so that they confine the eXtension ISA asclosely as is possible and yet allow the lateral movement of the holderIDA. The rear end of the extension I5A is peaked, having a centrallydisposed apex 42, and the inner surface of end wall 4I has acomplementary shape. The spring 23A normally holds the end wall 4Iagainst the end of the extension IEA, and by coaction between theircomplementary surfaces and the engagement of the thickened side portions49A of the block with the extension, act to normally hold the block andthe holder IIIA carried thereby, longitudinally centered. It will benoted from Fig. 6, which is a section through the upper portion of theblock 2BA, that the hole 2 IA, through which the pin I'IA passes, isenlarged to permit lateral movement of the block relative to the pin.

From the foregoing description it will be seen that direct longitudinaland lateral movement of the one holder with respect to the other isaccomplished about the pin I1, which is located on th'e longitudinalcenter or median line of the two holders, that separation of the holdersduring longitudinal movement is accomplished by coacting parts adjacentthis pin, and that longitudinal movement due to lateral movement, isaccomplished through the end of the extension I5, or I5A, and thecomplementary end ange or portion of the block 20, or 2BA, all of whichlie adjacent to this pin, thus freeing the articulator of widelyseparated parts for accomplishing such movements and making thearticulator compact and easy to manipulate, particularly in observingand relatively shifting models to determine their t under conditionsanalogous to those of the finished teeth in the mouth, as when bitingwith the front teeth or grinding with the rear teeth or molars.

In using the device, models are formed substantially as set out in ourprior Patent No. 2,094,903, during this forming operation the nuts 24and 25 preferably being clamped to rigidly hold the upper and lowerholders in their normal relation. The first models are made of plasterof Paris, or other comparatively soft dental investment material. Aftercompletion of these models the nuts 24 and 25 are released and the twomodels may be moved relatively to each other for examination and otherpurposes. In doing this, the concentration of central parts adjacent thepin I1 permit the thumb to be placed against the post I4, and theforenger around the model I2. By contraction of thumb and nger the lowerholder may be moved forward relative to the upperholder to bring thefront teeth into occlusion and enable the Vbite of the teeth to beexamined and, if necessary, correction be made to correct the bite. Inthis movement it will be noted that the screw 28 slides upward along theinclined portion I6 of the extension, separating the back teeth, as isdone by the equivalent movement of the jaws and permitting the frontteeth to be properly brought together, with the back teeth separated.With the front teeth in biting contact the front ends of the holders maybe laterally shifted and necessary correction in bite observed and made.

With the upper holder held in normally retracted position by the spring23 and properly centered by the spring and abutting parts, the rearteeth should be in perfect contact and, if not, the faults may beobserved and corrected. In such position one holder may be shiftedlaterally with respect to the other by suitable movement of the thumband finger. In such lateral shifting the flange 22, being in contactwith the rear end of the extension I5, advances the lower jaw relativelyto the upper Jaw for any movement away from a central position, theresulting movements conforming to those of the teeth in the mouth. Inthis action the lugs 30 limit the amount of lateral shifting. Wheneverthe models are released from manual pressure the spring 23 restores thetwo holders to their initial alignment. It will be understood also thatafter examination is made from one side by grasping post and model withthumb and finger respectively, that the articulator is usually reversedand post and model are grasped from the opposite side by finger andthumb respectively.

When completed both models, or either model is turned over to thelaboratory to make bridges, plates, or the like, as may be desired. Whenthe laboratory has completed its work the dentist may assemble thecompleted work in his articulator and examine the normal setting of therear teeth and their action, the bite of the front teeth, and such otherparts as may be desired.

What we claim is:

1. A dental articulator having a pair of model holders spaced apart, amember projecting from the rear end of a first said holder toward thesecond thereof and rearwardly bent to form an eX- tension, a portion ofthe surface of said extension adjacent said member, and facing thissecond of said holders, sloping rearwardly towards said second holder, apin positioned rearwardly of said sloping surface, secured to andprojecting from said extension towards and beyond said second holder, ablock, longitudinally slotted to receive said pin, disposed thereoverand against said extension, a nut on said pin adapted to retain saidblock, said block having a fianged portion complementary to and adaptedto engage the end of said extension, a spring secured to said rstholder, engaging and urging said fiange against said end, means hingingthe rear end of said second holder to the laterally opposite sides ofsaid block, and an adjustable screw threadedly engaging said secondholder and adapted to rest on said sloping surface.

2. A dental articulator having a pair of model holders spaced apart, amember projecting from the rear end of a rst said holder toward thesecond thereof and terminating in a rearward extension having a squarelyfaced end, a pin secured to and projecting from said extension toward,and beyond, said second holder, a block, longitudinally slotted toreceive said pin, disposed thereover and against said extension, a nuton said pin adapted to retain said block, said block having a flangedportion complementary to, and adapted to engage, the end of saidextension, a spring secured to said rst holder, engaging and urging saidflange against said end, and means hinging the rear end of said secondholder to the laterally opposite sides of said block.

3. A dental articulator having a paii` of model holders spaced apart, amember projecting from the rear end of a first said holder toward thesecond thereof and terminating in a rearward extension, a pin secured tosaid extension and projecting therefrom toward, and beyond, said secondholder, a block, longitudinally slotted to receive said pin, disposedthereover and against said eX- tension, means on said pin adapted toslidably retain said block, said block having a flanged portioncomplementary to the end of said extension, and adapted to cooperatewith said end to longitudinally center said block, a spring secured tosaid first holder, engaging and urging said flange against said end, andmeans hinging the rear of said second holder to the laterally oppositesides of said block.

4. A dental articulator having upper and lower model holders spacedapart, a member projecting upward from the rear end of said lowerholder, said member being bent into a substantially horizontal extensionand having a substantially hat rear end, a pin secured to and projectingupward from said extension beyond said upper holder, a block having asubstantially flat rear end and longitudinally slotted to receive saidpin, disposed over said pin and against said extension, means on saidpin adapted to slidably and oscillatably retain said block, a flatspring secured to said lower holder, engaging against, and urging saidblock forward, means hinging the rear end of said upper holder to thelaterally opposite sides of said block; and means carried by said blockand co-operating with the flat end of said extension, for retractingsaid block and first holder relatively to said second holder on relativelateral movement of said holders.

5. A dental articulator having a pair of model holders spaced apart, therst of said holders having a substantially iiat rear end, a membercentrally disposed at the rear end of the second of said holders, saidmember having a substantially ilat rear end, means pivoting said secondholder to the opposite sides of said member, means, centrally disposedadjacent the rear end of said rst holder, slidably and` oscillatablymounting said member on said first holder, resilient means carried bysaid rst holder engaging against the rear end of said member and urgingsaid member forward relatively to said iiiislt holder, and said secondholder into longitudinal alinement with said first holder, and meanscarried by said member and cooperating with the flat rear end of saidrst holder, for retracting said second holder relative to said firstholder on relative lateral movement of said holders.-

RALPH A. PITTMAN. JOSEPH A. GARDNER..

